Code comments have always been in discussion, whether one should have comments in code or not. Personally, I believe in not having comments and writing code in a way that makes things obvious. But, there are cases when you do want to add minor comments.

Be careful if you are adding comments, there is no way to check if your comments are correct or not!

In this post, I’ll be discussing when to use/not use comments in code -

When to use comments

Code Tells You How, Comments Tell You Why

• Explain something which is not obvious to user like explaining architecture.

• Adding TODOs for developing later

  func UserGetHandler(w http.ResponseWriter, r *http.Request) {            
     // TODO: Add google analytics     ...  
  } 

• Documentation comments - for someone who wants to use your code but not really work on it. These are useful in generating documentation websites from code itself. Eg. Go libraries.

• License comments - required due to legal issues.

When to not have comments

Best code comment is to not write it at all!

• Don’t add comments which are redundant

// Import logger package 
import "github.com/google/logger"

In the above example, it is totally irrelevant to add the comment. Import statement already signifies what the comment says.

• Avoid comments which can be code changes

func getSum() {       
    // initializing value as 10 - BAD!     
    valueOne := 10 
}